In general, compared to a natural marble, artificial marbles made of acrylic resin have various advantages, such as a fine external appearance, a high processability, a lightweight, and a high strength, thus being widely used as materials for counter tables and other interior products. However, the artificial marbles have a limit to express a similar pattern to that of the natural marble or granite from the general combination of single colored opaque chips.
The artificial marbles made of acrylic resin are manufactured by mixing a filler, such as aluminum hydroxide, calcium carbonate, or silica, other pigments, and a hardening agent to a syrup mixture, which is obtained by mixing a monomer, such as a methylmethacrylate, with polymethyl methacrylate, casting the mixture using a forming die or a continuous steel belt, and hardening the obtained product.
In order to form a pattern and a color of the artificial marble, pigments and chips are used. The chips are generally made of the same material as that of the artificial marble. However, if necessary, the chips are made of a thermoplastic resin, such as polyvinyl chloride (PVC) or polystyrene (PS), or a thermosetting resin, such as epoxy resin or unsaturated polyester. At least one pigment is put into a composite for the artificial marble, and the composite for the artificial marble is manufactured into a flat plate through the same process as that of the conventional artificial marble, and is crushed into chips having various sizes.
Chips, which are used to prepare the conventional artificial marble, contain an inorganic filler, and have excessively low transparency regardless of the material of the chips, thus having a limit to achieve a transparent effect.
In case that chips, which do not contain an inorganic filler, are used, the chips float on the rear surface of the artificial marble (the surface of the artificial marble not contacting the steel belt), due to a difference of specific gravities, and do not harmonize with other chips, and the prepared artificial marble is easily damaged due to a difference of chip distribution between upper and lower portions.
Further, in this case, when the rear surface of the artificial marble, from which transparent chips are exposed, is used as a product surface, the artificial marble has problems, such as generation of pin holes due to air bubbles and problems regarding surface physical properties.
Korean Patent Registration No. 553603 discloses an acrylic artificial marble using chip in chip. This artificial marble also contains an inorganic filler, thus having low transparency.